Find and deletes lines

Hi Guys,

Is there way to delete an entire line from the entire file.
I'm editing an epub, and I want to delete every line 14 from the entire book.

And is there a way to delete
<p> Chapter 123: Random Chapter Name </p>
<p> Chapter 124: Random Chapter Name </p>
<p> Chapter 125: Random Chapter Name </p>

all in one go. Instead of going to each chapter and deleting that line.

Sorry, I cant think of a better way to explain it